How to tell if Cham is drinking

Just got my first Cham over the weekend, a 4 month old male Jackson. He's eaten about 4-5 small Dubias each day but I haven't seen him drinking. I've been hand misting with warm water until I can make a water heater for my mistking. Every time I mist however, he turns from light green to brown and sometimes almost black. I try not to directly spray him and just spray the live plants around him but haven't see him drink any water. Without actually seeing him drink, is the only way to monitor hydration from examining the feces? Also sometimes after chewing food he will rear back and point his mouth towards the top of the cage, is this just helping the food go down? I've attached a picture of him doing this.

Okay I see you've got a screen like me. I just recently got my Meller Cham, I was worried about the same... He would not drink from leaves or when I sprayed him, he actually gets pissy when I directly spray him (which makes sense I would too if it were me)

What I started doing was misting from the top of the cage from the outside in. As it hits the mesh it sprinkles and feels more like rain I suppose? It also builds up water on the mesh that will eventually drop (Just like water falling off a leaf)

It takes about 2 minutes of me doing that before he starts to drink. He'll open his mouth then gulp and close, repeatedly. That's at least how I know.

Yes and yes.

https://www.chameleonforums.com/poop-101-a-120171/